The user in Subject: created a Security Local group identified in New Group.

This event is logged on domain controllers for Active Directory domain local groups and member computer for local SAM groups. You can determine if the group is a domain or SAM group by comparing Group Domain: to the Computer: name. If they match you have a SAM group, if they differ you have a domain group.

Active Directory

In Active Directory Users and Computers "Security Enabled" groups are simply referred to as Security groups. AD has 2 types of groups: Security and Distribution. Distribution (security disabled) groups are for distribution lists in Exchange and cannot be assigned permissions or rights. Security (security enabled) groups can be used for permissions, rights and as distribution lists.

A domain local group means the group can only be granted access to objects within its domain but can have members from any trusted domain.

Local SAM

All groups are security groups in the computer's SAM. Local SAM groups can be granted access to objects on the local computer only but may have members from the local SAM and any trusted domain.

Subject:

Account Domain: The domain or - in the case of local accounts - computer name.

Logon ID is a semi-unique (unique between reboots) number that identifies the logon session. Logon ID allows you to correlate backwards to the logon event (4624) as well as with other events logged during the same logon session.